The calculated distance (air line) between Sankt Gallen and Zürich (Kreis 3) is approximately 41 miles respectively 66 kilometers.
By car or train, the actual journey to Zürich (Kreis 3) is certainly longer, as only the direct route (as the crow flies) between Sankt Gallen and Zürich (Kreis 3) has been calculated here.
Air line (approximately)
66 kilometers
36 nautical miles